In the problem to the left, if Tim mows 9 lawns this week, by how much will he have exceeded his goal?

Answer:
Step-by-step explanation:
a - number of lawn that Tim needs to mow
310 < 120 + 30a
190 < 30a
6.333 < a
a > 6.333
Tim needs to mow at least 7 lawns to earn more than $310